NEW YORK – Early in his big league career, George Lombard Jr. has provided glimpses that illustrate why the Yankees are banking on him as their shortstop of the future. Now he has etched his name alongside one of the greats of the franchise’s storied past. Lombard became the youngest Yankee to hit a grand slam since Mickey Mantle, clearing the right-field fence with a third-inning blast that helped power a 6-1 victory over the Rockies at Yankee Stadium. “It’s pretty cool,” Lombard said. “It’s definitely a little different from the first home run. A grand slam is cool. It was a big swing to put us in front and give us a good lead so we could win today.” The Yankees had not hit a grand slam all season until Lombard connected with Tomoyuki Sugano’s 86.6 mph slider, launching an opposite-field drive that cleared the right-field wall for a Statcast-projected 353-foot blast. Lombard was 21 years and 99 days old when he took the field on Wednesday. Mantle hit two grand slams at younger ages: 20 years, 280 days on July 26, 1952, at the Tigers, and 20 years, 283 days on July 29, 1952, at the White Sox. “It’s obviously pretty special,” Lombard said. “That’s up there – a legend in the game, and especially here.” Additionally, Mantle and Lou Gehrig are the only other Yankees since 1920 to have at least four RBIs in a game at a younger age than Lombard. Luis García Jr. and Cody Bellinger also homered for the Yankees (83-62), who have won seven of their past 10 games to move a season-high 21 games over .500. They remain four games behind the Rays (87-58) in the American League East.